atrioventrikulaarsõlm

The atrioventricular node, or AV node, is a crucial component of the heart's electrical conduction system. Located in the interatrial septum of the heart, near the junction of the atria and ventricles, it acts as a critical relay station for electrical impulses originating in the atria. These impulses, generated by the sinoatrial (SA) node, initiate atrial contraction.

Upon reaching the AV node, the electrical signal is briefly delayed. This delay is vital as it allows the atria to fully contract and pump blood into the ventricles before the ventricles themselves begin to contract. Without this pause, blood would flow inefficiently from the atria to the ventricles, and vice versa.

Following the delay, the electrical impulse is rapidly conducted through the AV node into the bundle of His, which then branches into the left and right bundle branches. These branches carry the impulse down to the Purkinje fibers, ultimately triggering ventricular contraction and the pumping of blood to the rest of the body. The AV node's ability to conduct and modify the electrical signal is essential for maintaining a coordinated and effective heartbeat. Its function can be affected by various conditions, leading to arrhythmias or heart block.